"I didn't feel that I could withdraw myself from that match," he said.

"I was unsure if I was going to be able to make it through the game. I felt that I didn't really have a choice if I wanted to keep on trying to be picked for Scotland and keep a good relationship with the coaches."

Lamont said he had witnessed players cheating concussion tests in a bid to be back in action before they are safely ready.

"Unless people identify the issues and come out and actually speak about it then things aren't going to change," he said.

"At the moment, it's a ticking time-bomb with the concussions. Sometimes you can be put under a huge amount of pressure, where you feel you have no other choice but to take the field, when you know there are possible consequences."

His first spell with Glasgow was from 2004 to 2007, when he scored 19 tries in 55 games before moving to Sale Sharks and then Toulon.

He left the French club to rejoin Glasgow in 2011 but only made six appearances in his second stint.

"I spent a whole season with a broken scaphoid when I was at Toulon and I was refused a scan on it," added Lamont. "They just kept playing it down as something insignificant, whereas effectively I was running the risk of arthritis in later life by not having it fixed."